Agricultural vehicles, such as planters towed by tractors, are often employed to distribute materials such as seeds, fertilizers, pesticides, other chemicals and other materials along the ground as they travel. Commonly, a slurry of a given material is separated into finely-granulated particles by one or more “singulators” and then distributed in a highly controlled manner (e.g., one particle at a time) by one or more meters that are positioned at different locations along the vehicle.
In vehicles employing meters that are located relatively far away from the central tank or hopper in which a material is held, additional “nursing” systems have been implemented that facilitate the delivery of the material to the meters. Typically, nursing systems operate by picking up the material at a tank and then delivering, on demand, the material down one or more distribution lines to smaller reservoirs associated with the meters. When a smaller reservoir is low on material, the nursing system automatically starts to pick up additional material and fills the smaller reservoir, without any electronic or mechanical controls. Nurse distribution systems improve the feasibility of supplying multiple meters with material from a single central tank, and thus reduce the amount of time and labor required to keep the central tank filled, which improves the efficiency of planting and other agricultural operations.
In contrast to the operation of the singulators, which separate materials into particulate form to allow highly controlled delivery, nurse technologies deliver material from a first location (e.g., the tank) to a second location (e.g., a reservoir on a singulator/meter) as a slurry of particles. There are generally two types of nursing distribution systems—series and parallel nursing distribution systems. Exemplary series and parallel nursing distribution systems are shown in U.S. Pat. Nos. 6,047,652 and 6,267,067, which are respectively entitled “Seed Planter Distribution System” and “Nurse Receiver and Header for Air Seeders”, which respectively issued on Apr. 11, 2000 and Jul. 31, 2001, and which are each hereby incorporated by reference herein.
Relatively recently, there has arisen increased interest in the capability of distributing not merely one but more than one material from a given agricultural vehicle. As the size of farms has continued to increase, the need to be able to distribute different materials at different portions of the farms has grown. Additionally, as farming techniques have become increasingly sophisticated, the desirability of being able to switch over from distributing one type of material to distributing another type of material depending upon a variety of conditions (e.g., slope and other terrain conditions) has also increased. Further, as the size of farms has increased and the number of persons engaged in farming labor has decreased, the desire for large storage tanks on planters where a farmer can plant one large field with a first seed variety and then plant a second large field with a second seed variety, without stopping to fill tanks in between, has increased. The use of such large storage tanks potentially allows a farmer to plant all day without stopping.
While the distribution of multiple materials has increasingly become of interest, presently-available systems for allowing such distribution are unsatisfactory. One existing system employs a tank having two or more compartments that, depending upon the position of a divider mechanism, are respectively coupled to the same singulator located proximate the tank. Although this system allows for more than one material to be distributed, this system is disadvantageous because the multi-compartment tank is difficult for farmers to fill and additionally because the amount of material that can be stored in any given compartment of the tank is much less than the amount of material that ordinarily would be stored in the tank in the absence of such compartmentalization. Further, because the singulator is located close to the tank (rather than at the row units), the amount of accuracy in controlling seed distribution afforded by the singulator is reduced.
Other existing systems employ two tanks on the agricultural vehicle, each of which can carry its own particular material. However, in such systems (which are typically implemented on planters), the two tanks are respectively coupled to first and second sets of meters that are respectively positioned on opposite sides of the planter. Consequently, while these systems allow for two different materials to be distributed (even at the same time) by a planter, the systems are typically only operated in this manner when the operator wants to continuously plant different materials, since switching back and forth would be impractical.
Although, with respect to these systems having two tanks, it is in some circumstances possible to alter which side of the planter distributes which material by rearranging the lines coupling the tanks to the row units, such an alteration process typically is impractical. In particular, the alteration process typically requires that an operator physically disconnect and reconnect the lines coupling the tanks to the row units, which is a slow and arduous operation.
Accordingly, it would be advantageous if a new system for distributing materials from an agricultural vehicle was developed that made it possible for each of two or more different types of materials to be easily distributed from all of the row units (or meters) of the vehicle. It further would be advantageous if such a new system made it easy for an operator (or a control device) to easily and rapidly switch the type of material being distributed by the vehicle. It further would be advantageous if, despite being able to distribute two or more materials, the new system was capable of distributing each of the materials in an accurate, controlled manner. It additionally would be advantageous if the new system was capable of distributing large amounts of each type of material.